1. Field of the Invention
The present invention relates generally to an additional transmission/reception channel matching apparatus for a mobile communication terminal, and, more particularly, to a transmission/reception channel matching apparatus for a mobile communication terminal and a mobile phone test equipment that is capable of matching the transmission and reception channels of the mobile phone test equipment for measuring the call quality of the mobile communication terminal with additional serial communication channels, which that may vary with each mobile communication terminal.
2. Description of the Related Art
With the rapid development of mobile communication network technology and the popularization of mobile communication terminals, most people are using mobile communication terminals. Accordingly, mobile communication terminal technology is developing, and various functions are added or provided due to competition between mobile communication service providers to satisfy users' various demands. As an example, mobile communication terminals equipped with a Digital Multimedia Broadcasting (DMB) function enjoy such popularity that they account for an overwhelming majority of newly commercialized terminals.
Such mobile communication terminals are becoming personal multimedia devices because high-quality display and sound and high-capacity memory are demanded due to the provision of various additional functions and various types of content. Mobile communication service providers need to measure the call quality of terminals in order to manufacture terminals having superior performance, and mobile communication network operators need to measure call quality in order to measure and optimize the performance or state of provided mobile communication networks.
In a method of measuring call quality, a mobile communication terminal is connected to a mobile phone test equipment, and the mobile phone test equipment transmits a transmission signal for the measurement of call quality to the connected mobile communication terminal. The mobile communication terminal receives and processes the transmission signal and transmits a relevant reception signal to the mobile phone test equipment, and the mobile phone test equipment can measure call quality by analyzing the reception signal.
The connection between the mobile phone test equipment and the mobile communication terminal is set up chiefly through a serial communication port provided in the mobile communication terminal. The functions of respective pins of the serial communication port are standardized in accordance with the Korean Ministry of Information and Communication standard, and the functions of the respective pins are listed in the following Table 1:
TABLE 124-pin Type Terminal Pin Map based on KoreanMinistry of Information and Communication StandardPin numberDescription1Battery ID2Hands-free mode3DSR4Power (+5.0 V)5Power (−5.0 V)6On switch7Audio In/PCM RX/DB RX8Option/PCM clock9Option/PCM sync10Option (USB RX)11Audio In/PXM RX/DM RX12Power GND13RXD14TXD15Option/USB TX16USB Power (+5.0 V/+3.3 V)17DCD18RI19Power GND20RTS21Power (+4.2 V)22Power (−4.2 V)23CTS24DTR
Table 1 summarizes the functions of respective pins provided in the serial communication port of a mobile communication terminal based on the Korean Ministry of Information and Communication standard. As described in Table 1, the unique designated functions of all 24 pins, except for pin Nos. 7, 8, 9 and 11, have been standardized, and pin Nos. 7, 8, 9 and 11 are defined as option pins that can be freely used by mobile communication terminal manufacturers.
Accordingly, each of the terminal manufacturers, who manufacture products using additional serial communication channels, except for pin Nos. 13 and 14 used for standard serial communication, (representative examples include combined CDMA/WCDMA terminals and products in which DM and data communication ports are different from each other), selects two pins from among option pin Nos. 7, 8, 9 and 11 and sets and uses the two pins for relevant additional serial communication channels. Table 2 shows the use of the additional serial communication channels of representative mobile communication terminals.
TABLE 2Company Company S'sCompanyCompany K'sSPH-K'sK'sClassificationW1xxxS3xxxEvD0-xW2xxxTX2No. 9No. 11No. 7 No. 9RX2No. 8No. 7 No. 11No. 8
However, since each manufacturer freely selects two pins from among option pins and sets the two pins for communication channels for each mobile communication model, a disadvantage arises in that dedicated connection cables corresponding to each mobile communication terminal must be provided in order to measure the call quality of various mobile communication terminals and mobile communication networks. That is, since pins set for transmission and reception channels in the terminal W1xxx of company K are different from pins set for transmission and reception channels in the terminal SPH-S3xxx of company S, as shown in Table 2, it is impossible to measure the call quality of the two terminals using the same connection cables.